Select the combination of letters that when sequentially placed in the blanks of the given series will complete the series.
c k _ g k c _ t _ k _ k t g _ c k _ g k

A

t, k, g, c, k, t

B

t, k, g, c, c, t

C

t, g, k, c, k, t

D

t, k, c, g, k, t